Timing checking device



Dec; 1946. F. D. WARBURTON 2,413,126

TIMING CHECKING DEVICE Filed Aug. 29, 1944 v rkg l I 4 v .INVENTOR.

3L7: cu k l7 11/ 11b Mr #011 Q 7 BY Patented Dec. 24, 1946 UNITED STATESPATENT OFFICE TIMING CHECKING Frank D. Warburton, Southgate, Calif;Application August 29, 1944, Serial No. 551,754

1 Claim.

This invention has to do with devices for checking the ignition timingin relation to the dead center position of internal combustion enginesand in some respects is in the nature of an improvement upon theinvention disclosed in my copending application Serial No. 527,163,filed March 20, 1944.

In my said copending application I disclose a device which has, inconjunction with visual means for indicating the sparking point in theignition system of an internal combustion engine, audible means forindicating the direction of travel of the piston, as well as forindicating when the piston in its movement reaches dead center. Mypresent invention accomplishes those purposes but by means of asimplified, more economical and more universally useful device, it beingan object of the present invention to provide, in such a device, aresilient compressive means for mounting the device in the spark plugport of a cylinder to permit a single device to be readily installed ina port of any size.

It is a further object to provide in such a combination a simplifiedmeans for providing the audible signals as well as a simplified meansfor incorporating the audible signalling elements in the structure.

Additional objects of the invention are to provide an extremely simpledevice which requires but a minimum of parts, which is economical ofmanufacture and extremely durable.

By way of explaining my present improvements I shall now describe one ofits presently preferred embodiments for which purpose I shall refer tothe accompanying drawing, in which:

Fig. 1 is a side elevation of my device mounted in the spark plug portof an internal combustion engine, the latter being shown fragmentarilyin section;

Fig. 2 is a longitudinal section of my device; and

Fig. 3 is a section on line 3-3 of Fig. 2.

Referring now to the drawing, the numeral 5 denotes a cylinder head ofan internal combustion engine, having the usual cooling fluid jacket 5,a crank l, a piston 8, a connecting rod 9 and a spark plug port Hi. Thepiston is shown in the dead center position.

Generally denoted by the numeral l5, my timing checking device comprisesa resilient compressible base portion 20 which is preferably made ofsoft rubber of a synthetic type which is relatively unaffected by oilsand greases. The base is frusto conical in shape, having a longitudinalpassageway 2| whose lower end communicates 2 with the combustionchamber, the base being adapted to be forced into spark plug port In ina manner to have fluid-tight fit therein.

The top end of the passageway 2| has an enlarged diameter portion 22 toreceive the bottom reduced end of a cylindrical casing which may be madein two sections 25a, 26b, frictionally fitting together at 26.

In the upper end of the casing an electric light bulb socket 38 issecured, carrying a bulb 3!. The socket has connected to it twoelectrically conductive wires 34, 35, one of'which has on its free end acontact element not shown, adapted to be grounded to some metal part ofthe motor, and the other of which has a contact element, likewise notshown, which may be connected to the wire leading from the conventionaldistributor to the spark plug which would normally fit into the port I0occupied by the checking device. Illumination of the bulb is visiblethrough a window 36 in the casing.

Within an annular inwardly opening groove 38 formed in the side wall ofthe base I mount a round disc 39 whose peripheral edge is retained inthe groove 38. Two elongated openings 40, 4|, are provided through thedisc. In normal closing relationship to the opening 40 I secure on thetop of the disc a vibratory tone-producing reed 65, one end of the reedbeing secured to the disc by means of a rivet 46. In normal closingrelationship to opening 4| I secure on the bottom face of the disc asecond vibratory tone-producing reed 59, one end of which is secured tothe disc by rivet 5|. Reeds 45, 58 have relatively differenttone-producing qualities so that a tone produced by one may be audiblydistinguished from a tone produced by the other.

The disc 39 may be installed in the base by suitably flexing the baseand is held securely in position by the resiliency of the material ofthe base.

In operation, upward movement of the piston in the cylinder will, by theresultant compression, force air outwardly through the passageway 2| ofthebase, and the air passing outwardly through the opening to past theyieldable reed will vibrate the latter to produce an audible signal.When the piston reaches dead center in its upward movement, the audiblesignal will be momentarily silent until the piston begins its downstroke. The resultant vacuum in the combustion chamber created by thedownward stroke of the piston will draw air into the combustion chamberthrough opening 4! to vibrate reed 50. Inasmuch as, if properly timed,the distributor 3 will close the circuit to the lamp 3| during the timethe audible signal is silent, if the lamp 3| should be illuminated atany other time the operator will know that the motor is not properlytimed and he will readily discover whether the sparking point is tooearly or too late in relation to the dead center position of the piston.

While, in the foregoing, I have resorted to considerable detail ofstructure and association of parts in describing a particular example ofmy invention, I wish it to be understood that I have done so merely tomake my invention understood and that I do not limit my invention tosuch details. On the contrary, my invention is only to be limited asappears in the appended claim.

I claim:

In a timing checking device adapted to be temporarily secured in thespark plug port of an internal combustion engine, a hollow body, an

electric bulb mounted in the body, electrically conductive meansassociated with the bulb and extending through the body for connectioninto the ignition circuit of the engine, a neck member secured axiallyto the lower end of the body and having a peripheral surface engageablein said spark plug port, said neck member having an axial bore forproviding air communication between the engine and the interior of thebody, an air-actuated signalling element mounted transversely of thebore, and common means for providing ingress and egress of air into andfrom the body and rendering visible from the exterior of the bodyillumination created by the bulb, said means comprising a window in thebody adjacent the bulb and above the air responsive signalling element.

FRANK D. WARBURTON.

